The U.S. Army Corps of Engineers’ contractor began annual maintenance dredging of the federal navigation channel in Grays Harbor Inner Harbor Sunday, Jan.17, 2016.

Tacoma-based American Construction Co., is contracted for $4 million to dredge up to 475,000 cubic yards of material in the inner harbor near Aberdeen, Wash., working through 14 February 2016. American’s Patriot dredge will place material at the existing South Jetty nourishment site and Washington State Department of Natural Resources-managed Point Chehalis open water disposal site.

Inner harbor dredging is confined to the currently maintained -36 feet mean lower low water (MLLW) depth. As part of the Grays Harbor Navigation Improvement Project, a contract to dredge to the fully authorized -38 feet MLLW, is currently being developed. Corps officials expect to begin the next round of dredging operations in October, including the authorized additional two feet, in the vicinity of South Reach upstream to Cow Point Reach where the Port of Grays Harbor Terminal 4 is located.

Dredge and disposal sites need to be kept free of crab pots and other fishing, according to Corps Seattle District officials. The channel requires annual dredging to allow shipping from the Pacific Ocean to the navigation channel head at Cosmopolis, Wash. Shoaling, sedimentation filling in the channel, reduces the ability of ships to enter and leave safely under full load or during low tide conditions.

Seattle District officials work with state and federal agencies and Native American Nations to minimize harm to the aquatic ecosystem. They prepare a Biological Evaluation in accordance with the Endangered Species Act and Environmental Assessment in accordance with the National Environmental Policy Act.

Corps officials assure full compliance with the acts prior to starting. Potential dredging and disposal operations impacts are also avoided through implementation of U.S. Fish and Wildlife Service-designated timing restrictions. In addition, local crab fishermen assist by temporarily relocating during operations.